A rotary tool, such as an impact wrench, generally includes a housing supporting a motor, a drive mechanism driven by the motor, an output shaft having a first end adapted to engage a fastener and a second end adapted to engage the drive mechanism. In impact wrenches, the drive mechanism generally includes a hammer member, which periodically impacts the output shaft, rotating the output shaft about a central axis to hammer or drive fasteners into or remove fasteners from a work piece.